Accomplished Something…

[4metals]

In fairness I've not had a Metastannic problem for twelve years

That is because you do 2 things which need to be highlighted.

One, you return it to the solution before de NOx
Two, you never return it to the solution after filtering and beginning your drop.

A problem some refiners have is they think if it’s OK to do it on a small scale, it’s OK to over do it as well. You surely are talking a drop of stannous per test. I have seen refiners dropping gold and pick up a squeeze bottle full of stannous and squirt it into the solution to see if they are done. Then they wonder why their gold isn’t pure!

Personally I’m a drop of solution and a drop of stannous on a strip of filter paper guy. A refinery always generates a collection of waste for burning and recovery and the test papers go that route.

 

[Yggdrasil]

Certainly does- the ancient analogy of "you don't lose your gold until you throw it away" springs to mind. I don't do this when dropping, I do it prior to denoxxing. After denoxxing I keep all the tests, and put them in my next dissolve so they stay in the mix.

In fairness I've not had a Metastannic problem for twelve years Ygg. Thinking a process through and removing the potential problem before it becomes an issue is the way forwards here.

I was guessing the Tin in the stannous did leave a minute amount, but should not pose an issue.

 

[anachronism]

That is because you do 2 things which need to be highlighted.

One, you return it to the solution before de NOx
Two, you never return it to the solution after filtering and beginning your drop.

A problem some refiners have is they think if it’s OK to do it on a small scale, it’s OK to over do it as well. You surely are talking a drop of stannous per test. I have seen refiners dropping gold and pick up a squeeze bottle full of stannous and squirt it into the solution to see if they are done. Then they wonder why their gold isn’t pure!

Personally I’m a drop of solution and a drop of stannous guy on a strip of filter paper guy. A refinery always generates a collection of waste for burning and recovery and the test papers go that route.

As per the bold - exactly. I've seen the squirt it in approach too, and honestly shake my head when I do. You're paper based I'm spoon based and I think that provided the mechanisms are understood, then both have their merits. It's when they are not understood that the issues occur which brings me back to the point that we don't have to be fully fledged chemists to do this but in order to be the best we can be, we have to understand the chemistry that underpins the reactions we are carrying out.

Only then can we deal with problems, or improve our processes. Knowledge is power.

 

[Edwin Price]

Haven’t been refining lately due to family health issues. But I got back in the groove this weekend. Success!

 

[Edwin Price]

I did procure a torch stand so that I can now use two torches when melting powder.

 

[Edwin Price]

I also bought an old microwave to give it a try at melting once I get studied up on that method.

 

[4metals]

I also bought an old microwave to a try at melting once I get studied up on that method.

I was at a clients place a few years back and he had a microwave he was replacing and the guys in the back tried it and it worked well. The key is insulating the crucible and allowing the heat to build up properly. There are companies that sell kits to add to a microwave to do this here. I do not know the upper limit for this type of melt furnace.

 

[Edwin Price]

I was at a clients place a few years back and he had a microwave he was replacing and the guys in the back tried it and it worked well. The key is insulating the crucible and allowing the heat to build up properly. There are companies that sell kits to add to a microwave to do this here. I do not know the upper limit for this type of melt furnace.

I have a fire brick and insulation. Are any of the devices below capable of melting gold powder in a microwave?

 

[Edwin Price]

If not can I get some suggestions on what type crucibles to use. Thank you.

 

[goldshark]

If not can I get some suggestions on what type crucibles to use. Thank you.

A simple fire clay crucible is preferred, properly fired before hand in a fire environment.

 

[goldshark]

Sooo, while on the subject of microwave melting, here are a couple observations and questions about the process;
1. The micro waves heat the metal first, then the metal heats the crucible.
2. Does anybody know how hot a microwave will heat the metal to?
3. If the micro waves heat to an appreciable amount above the melting point, what is the loss percentage?
4. If you don't allow the crucible to heat to the melting temp of the metal, you will have the button freeze immediately upon removal of the microwave oven.
I would like to hear from others the does and don'ts concerning microwave melting. I haven't seen much posted here, but then again, I didn't search .

 

[Edwin Price]

Can someone recommend a valid “kit” for smelting powder in a microwave? I appreciate all the info, but I don’t want to make any errors here. ty

 

[Yggdrasil]

Can someone recommend a valid “kit” for smelting powder in a microwave? I appreciate all the info, but I don’t want to make any errors here. ty

I have never seen such a kit.
You can make it yourself though.
Withe insulating firebricks and a crucible inside.
I think there are videos out there that can hint about designs.

 

[4metals]

The link I posted above from the Gold Rush Trading Post has a video and a good photo of what is supplied with the kit. From what I gather they do not sell them anymore for whatever reason. Maybe a phone call would be helpful.

 

[Yggdrasil]

The link I posted above from the Gold Rush Trading Post has a video and a good photo of what is supplied with the kit. From what I gather they do not sell them anymore for whatever reason. Maybe a phone call would be helpful.

Interesting indeed

 

[Martijn]

Can someone recommend a valid “kit” for smelting powder in a microwave? I appreciate all the info, but I don’t want to make any errors here. ty

Here is a video about it. Pretty amazing.

 

[Edwin Price]

Here is a video about it. Pretty amazing.

Thank you!

 

[Edwin Price]

The link I posted above from the Gold Rush Trading Post has a video and a good photo of what is supplied with the kit. From what I gather they do not sell them anymore for whatever reason. Maybe a phone call would be helpful.

Thank you

 

[Edwin Price]

Try not to laugh too much at the quantity, but I believe this powder in a 1000 cc beaker to be pretty much pure gold. It was refined twice. I have two other beakers precipitating out right now too. All solutions used tested positive solid dark black with stannous chloride. No purple this time.

 

[Edwin Price]

Try not to laugh too much at the quantity, but I believe this powder in a 1000 cc beaker to be pretty much pure gold. It was refined twice. I have two other beakers precipitating out right now too. All solutions used tested positive solid dark black with stannous chloride. No purple this time.